Free Technical Repair Tip: Tube replacement notes: The 6KG6/EL509 tube still made in Europe & Russia can be used as a heavy duty replacement for a 6LQ6 & many other "sweep" tubes. A 6KG6 is about 1/2" taller than a 6LQ6 so you first need to see if you have room for a conversion. The socket pin connection change is easy: Pin 3 of the 6LQ6 was the cathode while pin 9 of a 6KG6 is the cathode; move the lead formerly on pin 3 to pin 9 (not used on the 6LQ6); add a jumper from pin 3 to pin 2 on the socket. You may need to squeeze or swap the plate cap to fit the 6KG6. The pins of a 6KG6 are a little larger than the pins of a 6LQ6; however--with a used socket--the pins just fit a little tighter in the socket! In some units it may be necessary to shorten the "pi-net" coil by 1 turn or add a 100 to 200pf Silver Mica 1000V capacitor in parallel across the antenna-load capacitor to bring the "tune" & "load" capacitors into the proper tune-up positions.

GE 8908 (HyGain 760002) tube replacement: The best choice to replace the no-longer-available 8908 is to change the socket and plate cap to use a 6KG6/EL509. Both tubes are the same height and both are rated at 40W plate dissipation. The Novar sockets we have available fit in the same size hole as the octal socket you are removing so these are a direct bolt-in replacement--no drilling necessary to mount the new sockets! Virgin Novar sockets need to have the pin connector holes enlarged a little--use an awl or large needle--before you attempt to plug in the 6KG6/EL509 tubes.

8908 tube

6KG6/EL509 tube

Pin 1=G1

Pin 1=G1 (also--Pin 8=G1)

Pin 2=G3

Pin 2=G3 (also--Pin 7=G3)

Pin 3=G2

Pin 3=G2; (also--Pin 6=G2)

Pin 4=cathode

Pin 9=cathode

Pin 5=G1

Pin 8=G1 (also--Pin 1=G1)

Pin 6=G3

Pin 7=G3 (also--Pin 2=G3)

Pin 7=heater

Pin 4=heater

Pin 8=heater

Pin 5=heater

3/8" Plate Cap

1/4" Plate Cap

Free Technical Repair Tip: Substitution ideas for tubes in former "CB Linears" now owned by licensed ham radio operators6JB6A: generally interchangable with 6JF6, 6JU6, & 6KM6.6JE6/6LQ6: none available at old-cheap prices anymore! generally interchangable with 6ME6 & 6MJ6. In some "5-tube" units it is possible to rewire the heater pins (in series across 120VAC instead of parallel across 6.3VAC) to use 24JE6/24LQ6 tubes. In some "3 tube" or "6 tube" units it may be desirable to rewire sockets (three heaters in series across 120VAC instead of all in parallel across 6.3VAC) to use 40KG6 tubes; in many other units 6KG6 tubes are the best choice.6JG6A: generally interchangable with 6JR6, 6JT6A, & 6KV6A.6LF6: generally interchangable (no changes) with 6KD6, 6LX6, & 6MH6; also (may require minor changes?) 6JS6C, 6KN6, 6LB6, 6LR612JB6A: units with (2) tubes can have heaters rewired in series to use 6JB6A etc.8950 & M2057: Obsolete 12 volt duodecar tubes; In most cases the heater pins can be rewired in series-parallel to use similar 6 Volt tubes such as 6KD6, 6LF6, 6LX6, or 6MH6.8975: was used in Hygain Galaxy linear. the ratings are similar to the 6KG6 tube; the 8975 is a 12 pin tube but the 6KG6 is 9 pin that has slightly larger pins than the 481A4 Novar sockets we have in stock. Substitution for the 8975 requires installing new tube sockets--see also the note about the 8908 replacement in the paragraph above.Purchase and read the BLACK BOOK OF CB LINEARS for specifications & more substitution ideas.